[PATCH 4.14 155/217] gpu: host1x: Check whether size of unpin isnt 0

[Greg Kroah-Hartman]

4.14-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Dmitry Osipenko <digetx@xxxxxxxxx>

[ Upstream commit ec58923215dbbeef59ee82923ee94d745f73db58 ]

Only gather pins are mapped by the Host1x driver, regular BO relocations
are not. Check whether size of unpin isn't 0, otherwise IOVA allocation at
0x0 could be erroneously released.

Signed-off-by: Dmitry Osipenko <digetx@xxxxxxxxx>
Signed-off-by: Thierry Reding <treding@xxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 drivers/gpu/host1x/job.c |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

--- a/drivers/gpu/host1x/job.c
+++ b/drivers/gpu/host1x/job.c
@@ -686,7 +686,8 @@ void host1x_job_unpin(struct host1x_job
 	for (i = 0; i < job->num_unpins; i++) {
 		struct host1x_job_unpin_data *unpin = &job->unpins[i];
 
-		if (!IS_ENABLED(CONFIG_TEGRA_HOST1X_FIREWALL) && host->domain) {
+		if (!IS_ENABLED(CONFIG_TEGRA_HOST1X_FIREWALL) &&
+		    unpin->size && host->domain) {
 			iommu_unmap(host->domain, job->addr_phys[i],
 				    unpin->size);
 			free_iova(&host->iova,